Maintenance-Free Global Data Storage

OceanStore is a persistent data store designed to scale to billions of users and exabytes of data. Maintaining such a system requires automatic software support. A large system like this is hard to tune for performance; moreover, its size indicates that some subset of its components will be failing at any one time. To that end, OceanStore is designed to be largely self-maintaining. It recovers from server and network failures, efficiently incorporates new resources, and adjusts to changing usage patterns, all without manual intervention. This article describes the approach and presents a general architecture for systems of this type. A prototype OceanStore system is currently under construction at the University of California at Berkeley.Keywords: distributed storage, security, archival, introspection, wide-area, automatic repair, routing, fault tolerance.